I use a Earlybird Thermonic Culture valve Pre - it is huge (4U) and excelent for my
RoyerSF-12.

Where you get info on one I dont know, I bought it from a studio that wasnt using it much. Awsome.

Anyway my vote is for a 'big unit'. Fletcher probably could shed light on this, perhaps its a giant hand wound transformer that adds character to the sound, dunno ribbons need special 'help' electronicaly.

I've used both of those with exquisite results...I'd add the Pendulum MDP-1 to the list as well...almost in the same leauge sonically, couple extra features, slightly lower capital expenditure. I mean we are kind of talking about the difference between a Lotus and a Ferrarri at this level...I'd put the MDP-1 in there like a Porsche to the other two.

Generally, in that kind of a ballpark, you can't go wrong, just slightly different tone or texture.

One of the under-appreciated benefits of gear made by small companies:

In addition to the quality of the actual unit, you also get the benefit of having access to the designer / builder of your preamp. And in the case of guys like Doug Fearn, that only adds to the value of your purchase. Compare that to calling your typical customer support number(1-800-who-cares)

I'm normally a big fan of vintage (old?) equipment, but the companies you are considering offer advantages that no vintage gear can match. Which ever one works best for your particluar needs, I don't think you could go wrong with any of them.

Fletcher, judging from the color and price, DW Fearn should be the Ferrari...
Hollywood-steve, that's true. Doug Fearn contacted me personally and he at no cost would add o +6db switchable boost to its VT2 for using with ribbon mics... I was able to reach almost personally Tim de Paravicini (EAR) for the same purpose ... unbelievable !